Steam generator



July 27, 1954 s. B. HULL 2,634,662

' STEAM GENERATOR Filed Sept. 20, 1952 5 Sheets-Sheet 1 IN VEN TOR.

Stuart 5" Hull ATTY.

y 27, 1954 s. B. HULL 2,684,662

STEAM GENERATOR Filed Sept. 20, 1952 3 Sheets-Sheet 2 BURNER FUEL 37 37a A R 55a 4/ i BLOWER FUEL FILTER 42 3 SAFETY SHUT OFF WA 4 v INVENTOR.

Stuart 5' Hull WJJM U.

y 1954 s. a. HULL 2, 8 ,66

STEAM GENERATOR Filed Sept. 20, 1952 3 Sheets-Sheet 3 33 1,8 D/FILTER 22 CONDENSATE FILTER 23 M I 4 W TO FUEL SHUT OFF l 46 I PRESSURE GA.

[ STEAM STEAM TEMP. I

STEAM PRESSURE SAFETY VALVE 52 IN V EN TOR.

Stuart B- HLIZZ ATTY.

Patented July 27, 1954 UNITED STATES OFFICE STEAM GENERATOR Stuart B. Hull, Butler, Pa., assignor to Hull Resurfacing Company, Butler, Pa., a partnership 2 Claims.

This invention relates to steam generators, and an object is to produce a simple and efficient steam generator which is simple in construction and operation, capable of generating steam quickly and economically, controllable so that the characteristics and volume of the steam generated or discharged may be varied, and capable of being portable and self-contained.

Another object is to produce a steam generator of the above type embodying a fluid fuel burner, the source of air to such burner also delivering pressure fluid on top of the fuel reservoir or tank, to aid in the delivery of the fuel to the burner.

Another object is to produce a steam generator which is compact and self-contained, and may therefore be transported as a unit from place to place, and to equip such generator with automatic means preventing the flow of fuel'to the burner in case the water pump or water pressure to the steam generating coils is reducedor fails.

Other objects and advantages of the invention will hereinafter appear, and for purposes of illustration but not of limitation, an embodiment of the invention is shown on the accompanying drawings, in which Figure l is a side elevation of an automobile truck equipped with the steam generator according to this invention; 7

Figure 2 is an enlarged rear end elevation of the truck and associated parts shown in Figure 1;

Figure 3 is a longitudinal sectional elevation showing the water tank," the steam generating coils, and the fuel burner associated therewith; Figure 4.-.is a-diagrammatic View showing the fuel burner and the manner in which fuel is delivered thereto, the blower and piping for delivering air under pressure to the fuel tanks;

Figure 5 is a diagrammatic view of the manner in which steam is generated, and the path of travel of the water from the tank or reservoir to the steam generating coils and the return of condensateto the tank; and

Figure 6 is an enlarged sectional view of the burner fuel shut-off device.

The illustrated embodiment of the invention comprises an automobile truck it which is mounted onrubber-tired Wheels H. Suitably mounted upon the truck chassis is a cylindrical tank 12 which has at its upper side, a cap closed filler'opening l3 and within the tank spaced from the side walls thereof is a longitudinally elongate tubular housing l4 lined'on the inside with suit able heat insulation material or; refractory lining. The rear end of the tube 14 projects slightly outside of the rearend of the tank l2 and the front end terminates in a flanged portion 25 which is integral with the housing and tank, the refractory lining for the housing also being employed for the flue I6 to which the adjacent end. of the housing it opens, a suitable stack being on the upper end of the fiue Hi. The projecting end of the housing 14 is closed by a closure plate i: suitably attached thereto.

Disposed within the housing it and extending from end to end are coils of tubing, there being an outer helical coil i8 and an inner helical coil I80, formed from a single length of tubing. These coils are preferably concentrically arranged with the inner coils iBa spaced inwardly from the outer coils it, in order to enable the flame from the burner intimately to contact both coils. It will further be observed from Figure 3 that the coils cross each other in substantially X formation, that is, a portion of the coil which extends downwardly and forwardly is in crossing relation to the opposite coil or the inner coil which extends downwardly and forwardly. This arrangement is such as to make the most efiicient use of the heat from the fuel burner which will be hereinafter described.

Referring now to Figure 2, water is introduced to the inner coil 180. from piping it which is connected to the high pressure side of a suitable water pump 26. Water is delivered to the low pressure side of the pump 20 by a pipe 2 l, a hand valve 22 and a filter 23 being incorporated in this pipe line. From the pressure side of the pump 2t extends a pipe 24 to the inner helical coil iii. A tube leads from the pipe E l to a pressure gauge 24 arranged at the rear or outer end of the water tank I2.

Extending from the outer coil i8 is a steam outlet pipe 25 from which a tube leads to a steam temperature gauge 26, another tub'e leading therefrom to a steam pressure gauge 2?. As shown, the gauges 24', 26 and 2'! are mounted on a panel 28 suitably arranged at the rear of the water tank 12 adjacent the upper portion thereof. From the pipe line 25 extends a riser tube 29 which has a safety valve 30 at its upper end. As shown, the pipe line extends downwardly and thence outwardly and adjacent its outer end is a depending pipe having a manual bleed-off valve 3!.

This steam generator is particularly adapted for use in heating tank cars, steam being de livered thereto from the outlet pipe 25 and since these tank'cars areprovided with an outlet fitting, the condensate therefrom returns to the water tank i2 through'a pipe 32 (Figure 5), a

filter 33, and into the filler opening l3 through a down-turned end portion as shown.

For creating the necessary heat for generating the steam, a burner 34 of the gun type projects into the housing l4 through the closure plate ll, air being delivered thereto through a vertically disposed pipe 35 which connects at its lower end to the outlet end of a blower 36. In this instance, two fuel tanks are employed which can be used alternately, and as shown, longitudinally elongate tanks 31 and 31a are disposed on opposite sides of the water tank 12 and from these tanks are gravity feed pipes 38 and 38a respectively. The gravity feed pipes extend to a common fitting 39, hand valves 40 and 4001, being provided on opposite sides of the fitting for controlling the flow of fuel from these tanks as will be readily understood. Depending from the fitting 39 is a manual valve controlled fuel drain 4|. A tube 42 extends from the fitting 39 to a safety shut-off valve device 43 and from that device, extends a tube 44 to the burner 34, a manual valve 45 being arranged in the tube 44 adjacent the burner. A branch tube 46 leads from the water pipe 24 on the high pressure side of the pump 20 to the safety shut-off device 43, as shown on Figure 4.

The shut-off valve device 53 comprises a housing 41 having a transverse passage 48, to the opposite ends of which connect the pipes 42 and 44. At one side of the passage 48 is a cylinder 49, the outer end of which is closed by a cap 50 held in place by screws. Reciprocable within the cylinder 49 is a piston 5| which has a depending slide valve 52 reciprocable within a way formed within the housing, the slide having an opening 53 adapted to be aligned with the passage 48. A coil spring 54 beneath the piston 5i normally holds the slide 52 in its up or raised position, closing oif the pipe 42 from the pipe 44. The tube from the water line 24 indicated at 46, leads to the closure cap 50. As a result of this arrangement, when a pump is operating, the pressure from the pressure side of the pump is transmitted to the device 43 through the tube 46, thereby depressing the piston 5| and placing the spring 54 under com pression. Depression of the piston 54 places the valve opening 53 to enable liquid to pass through the passage 48, thereby to feed fuel to the burner 34. In the event that the water pump 20 stops, or that the tank runs out of water, then the passage 48 will be closed and no fuel, such as oil, will be delivered to the burner nozzle.

In order to build up a pressure head on the fuel contained within the fuel tanks 31 and 31a,

branch pipes 54 and 54a lead respectively to these tanks from the air pipe 35. Thus so long as the blower 36 is operating, air may be delivered to the top of these fuel tanks and impose pressure on the fuel to assist the flow thereof to the burner. In the lines 54 and 540. are manual valves 55 and 55a so that one or the other of these tanks may be shut off from the air supply.

In order to drive the blower and hydraulic pump, an internal combustion engine 56 is mounted on the truck chassis at the rear end thereof and as shown, the engine is provided with a drive sheave 51 about which is trained a belt 58 which engages a sheave assembly on the blower shaft 59, a belt 60 leading from the sheave assembly to a sheave on the hydraulic pump 20. In this manner, the engine 56 drives the blower shaft from which power is delivered to the hydraulic pump by the belt 60, as will be readily understood.

A protective housing 6! is provided over the rear end of the machine covering the engines 56, blower, hydraulic pump and associated parts.

From the above description, it will be manifest that steam can be quickly and economically generated, and that steam used for whatever purpose is desired. As above mentioned, the steam can be used to advantage in connection with tank railway cars for loosening up bituminous material, tar and the like carried by these cars, the condensate being returned to the water tank. Other uses, of course, can be made of the steam generator, such as for cleaning the outside of buildings, removal of ice, etc. The proper operation of the machine enables different steam characteristics to be obtained. For example, if a small volume of dry steam is desired, then the internal combustion engine 56 is slowed down somewhat and greater amount of fuel is delivered to the burner. At other times it is desired to have a large Volume of wet steam, and in that connection, the motor is accelerated and the fuel supply is reduced. Other variations, of course, can be eflected by eifecting other adjustments. The safety of the system is insured by the fact that the burner will not operate in the event that the hydraulic pump is out of order or that the water supply has become exhausted. The efficiency of the system will be recognized by the fact that the nested helical tubes are disposed within a housing which is arranged within the water tanks, so that preheating of the water is effected in this manner, thereby accelerating the generation of steam and reducing the fuel required for the purpose, to a minimum.

Although the device is shown and described in connection with an automobile truck, it is not intended that the invention is so limited, even though the portability of the mechanism is a very desirable feature. Numerous changes in details of construction, arrangement and operation may be effected without departing from the spirit of the invention especially as defined in the appended claims.

What I claim is:

l. A portable steam generator comprising a water tank having a side wall and spaced end walls, said end walls having opposed apertures therethrough, a cylindrical tube extending through said water tank and having opposite ends respectively supported in the apertures in said end walls, one end of said tube being open and the other end being substantially closed, an enclosure over the end wall of said water tank adjacent the open end of said tube, said enclosure defining a flue chamber and having a flue outlet therein, burner means supported in the substantially closed end of said tube, a continuous length of tubing providing connecting inner and outer helical coils, disposed co-aXially within said tube and having adjacent free ends, a water input conduit between the free end of one of the coils and said tank, a water pump in said input conduit, a steam outlet connection leading from the free end of the other coil, a fuel tank supported exteriorily of said water tank, fuel supply conduit means leading from said fuel tank to said burner means, an air pump, means for feeding air from said pump to said burner means and to said fuel tank, a shut-off valve in said fuel supply conduit means, resilient bias means normally biasing said shut-off valve closed, and conduit means connecting said water input conduit from a point between said water pump and said one coil to said resilient bias means for overcoming said resilient bias means in response to pressure of water in said water input conduit, whereby to maintain said fuel supply conduit means open so long as water is supplied under pressure to said one coil.

2. A portable steam generator comprising an elongate cylindrical water tank having a cylindrical side wall and substantially flat end walls, said end walls having opposed apertures therethrough, a cylindrical tube extending lengthwise through said water tank and having opposite ends respectively supported in the apertures in said end walls, one end of said tube being open and the other end being substantially closed, a cylindrical enclosure over the end wall of said water tank adjacent the open end of said tube, said enclosure defining a flue chamber and having a flue outlet therein, burner means supported in the substantially closed end of said tube, a continuous length of tubing providing connecting inner and outer helical coils disposed co-axially within said tube and having adjacent free ends, a water input conduit between the free end of the inner coil and said tank, a water pump in said input conduit, a steam outlet connection leading from the free end of said outer coil, a pair of fuel tanks supported on respectively opposite sides of said water tank, fuel supply conduit means leading from said fuel tanks to said burner means, an air pump, means for feeding air from said pump to said burner means and to said fuel tanks, a shut-off valve in said fuel supply conduit means, resilient bias means normally biasing said shut-01f valve closed, and conduit means connecting said water input conduit from a point between said water pump and said inner coil to said resilient bias means for overcoming said resilient bias means in response to pressure of Water in said water input conduit, whereby to maintain said fuel supply conduit means open so long as water is supplied under pressure to said inner coil.

References Cited in the file of this patent UNITED STATES PATENTS 

